Heat oven to 350 degrees. Prepare cake batter as directed on package, using egg whites. Spoon batter into paper lined muffin cups. Fill each cup 1/2 full. Bake as directed on package. Cool cupcakes in pan for 15 minutes then pierce with two pronged meat fork at 1/4 inch intervals. Dissolve gelatin completely in boiling water. Gradually spoon over cupcakes. Refrigerate 3 to 4 hours. Frost with whipped topping. Draw umbrellas on cake with decorating gel and sprinkle with colored sugar, if desired. Makes 24 cupcakes.